This invention relates to improvements in surgically implantable inflatable devices.
Tissue expansion devices of the general type illustrated in Radovan et al. U.S. Pat. No. 4,217,889 are finding substantial use in reconstructive surgery. Such devices generally comprise an inflatable body having a remotely located inflation button or valve connected to the inflatable body by means of an elongated conduit. The body is placed subcutaneously in the area in which the tissue is to be expanded and the valve and connecting conduit are implanted to allow gradual introduction of fluid into the device by injection into the inflation valve at a site remote from the body itself. After gradual inflation at intervals of weeks or even months the tissue has been expanded to the point where a permanent prosthesis can be inserted or a skin flap formed as desired and the expander is deflated and surgically removed. It is believed by some surgeons that the use of a remote location for the inflation valve minimizes risk of infection in the vicinity of the implant which might occur at any time during the period of injection of further fluid. Similar implants in which the inflation valve is located on the wall of the inflatable body itself and which, of course, lack the remote valve feature, are also currently in use and are preferred by some surgeons. Similarly, inflatable permanent prostheses are sometimes implanted and filled and/or reduced after implantation.
Particularly when asymmetrically shaped implantable devices are used the surgeon sometimes finds that the direction which the inflation conduit and valve extend away from the unit do not correspond to the preferred direction for placement of the conduit and valve. Although the conduit is typically flexible the surgeon must guard against kinking it in changing direction and often would prefer to have a straight rather than curved conduit configuration for implanting. For the manufacturer and the hospital or clinic this may mean that a substantial number of devices of various configurations need to be manufactured and stocked to provide implants with and without remote valves and with remote valves extending from the inflatable portion of the device on conduits protruding at different angles.